Electronic Devices With Orientation Sensing

ABSTRACT

An electronic device such as a pair of headphones may be provided with left and right speakers for playing audio to a user. Control circuitry in the electronic device may play audio through the speakers in an unreversed configuration in which left channel audio is played through a first of the speakers that is adjacent to a left ear of the user and right channel audio is played through a second of the speakers that is adjacent to a right ear of the user or a reversed configuration in which these channel assignments are reversed. The headphones may have ear cups that house the speakers. Capacitive touch sensors, force sensors, and other sensors on the ear cups may measure ear shapes and finger grip positions on the ear cups to determine whether to operate in the unreversed or reversed configuration. Sensors may gather gestures and other user touch input.

This application is a continuation of U.S. patent application Ser. No.15/245,582, filed Aug. 24, 2016, which claims the benefit of ProvisionalPatent Application No. 62/209,517, filed Aug. 25, 2015, both of whichare hereby incorporated by reference herein in their entireties.

BACKGROUND

This relates generally to electronic devices, and, more particularly, toelectronic devices such as headphones.

Electronic devices such as headphones may contain wireless circuitry forcommunicating with external equipment. The wireless circuitry mayreceive music and other audio content from remote equipment. The audiocontent can be played back to the user with speakers.

Audio content is often provided in a stereo format. Stereo audio hasleft and right channels. If care is not taken, a pair of headphones maybe placed on a user's head in a reversed configuration. In the reversedconfiguration, left-channel stereo audio is played into the user's rightear and right-channel stereo audio is played into the user's left ear.This type of reversed audio may detract significantly from a user'sexperience. For example, if a user is watching accompanying videocontent, the reversed audio left-channel audio will not be properlysynchronized with on-screen content, which can be disorienting for theuser. Users may also face challenges when adjusting media playbacksettings while wearing headphones.

It would therefore be desirable to be able to provide improvedelectronic devices such as stereo headphones.

SUMMARY

An electronic device such as a pair of headphones may be provided withleft and right speakers for playing audio to a user. The left and rightspeakers may be housed in left and right portions of the headphones suchas left and right ear cups.

Control circuitry in the electronic device may play audio through thespeakers in an unreversed configuration in which left channel audio isplayed through a first of the speakers that is adjacent to a left ear ofthe user and right channel audio is played through a second of thespeakers that is adjacent to a right ear of the user or a reversedconfiguration in which the right channel audio is played through thefirst speaker that adjacent to the left ear and the left channel audiois played through the second speaker that is adjacent to the right ear.Capacitive touch sensors, force sensors, and other sensors on the earcups may measure ear shapes and finger grip patterns on the ear cups todetermine whether to operate in the unreversed or reversedconfiguration.

Sensors for measuring ear shape may be located on inner surfaces of theear cups. Sensors may also be located on opposing outer ear cupsurfaces. A peripheral strip of sensor elements may run along a curvedintermediate surface between the inner and outer cup surfaces. Gripdetection sensing may be performed using the peripheral strip of sensorelements. A user may supply touch gestures and other touch input totouch sensors on outer ear cup surfaces. User input may, for example, beused in adjusting audio playback volume and other audio playbacksettings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of an illustrative electronic device inaccordance with an embodiment.

FIG. 2 is a perspective view of an illustrative electronic device suchas a pair of headphones in accordance with an embodiment.

FIG. 3 is a cross-sectional side view of a portion of an electronicdevice in accordance with an embodiment.

FIG. 4 is a diagram of an illustrative capacitive touch sensor inaccordance with an embodiment.

FIG. 5 is a top view of an illustrative fabric of the type that may beprovided with conductive strands of material such as yams ormonofilaments to form a touch sensor in accordance with an embodiment.

FIG. 6 is a cross-sectional side view of a portion of a sensor withelectrodes separated by a compressible material in accordance with anembodiment.

FIG. 7 is a cross-sectional side view of the sensor of FIG. 6 in aconfiguration in which the compressible material has been compressed sothat the electrodes have moved closer to each other in accordance withan embodiment.

FIG. 8 is a cross-sectional side view of an illustrative sensor with twolayers of fabric separated by a compressible structure in accordancewith an embodiment.

FIG. 9 is a side view of an illustrative light-based sensor for anelectronic device in accordance with an embodiment.

FIG. 10 is a side view of an illustrative sensor with resistors inaccordance with an embodiment.

FIG. 11 is a cross-sectional side view of an illustrative sensor with anarray of compressible force-sensing elements in accordance with anembodiment.

FIG. 12 is a side view of a portion of a headphone with a ring-shapedsensor that runs around a central speaker area in accordance with anembodiment.

FIG. 13 is a perspective view of an illustrative headphone havingexternal surfaces that can gather input from a user's fingers or otherexternal objects in accordance with an embodiment.

FIG. 14 is a side vim of an illustrative headphone of the type shown inFIG. 13 in which a sensor is being used to detect a user's grip on theheadphone by analyzing the pattern of finger contacts between the user'sfingers and thereby discriminating between left-hand and right-hand grippatterns in accordance with an embodiment.

FIG. 15 is a diagram of output from an array of sensor elements that hasmade measurements on an adjacent body part of a user such as a user'sear in accordance with an embodiment.

FIG. 16 is a diagram of an illustrative radially symmetric sensorelement pattern for an ear shape sensor on a pair of headphones inaccordance with an embodiment.

FIG. 17 is a diagram of an illustrative electrode pattern for an earshape sensor such as a capacitive touch sensor having curved electrodessuch as concentric ring-shaped electrodes and radially extendingelectrodes that overlap the ring-shaped electrodes in accordance with anembodiment.

FIG. 18 is a diagram of an illustrative electrode pattern for the earsensor having concentric ring-shaped electrodes that have been bisectedalong a vertical line in accordance with an embodiment.

FIG. 19 is a diagram of an illustrative electrode pattern having fourquadrants of concentric ring-shaped electrodes in accordance with anembodiment.

FIG. 20 is a flow chart of illustrative steps involved in operating anelectronic device such as a pair of headphones having sensor structuresin accordance with an embodiment.

DETAILED DESCRIPTION

An electronic device may be provided with sensors that monitor how thedevice is oriented relative to the body of a user. The sensors may, forexample, include touch sensors and other sensors that monitor how a useris holding a pair of headphones or other device while putting theheadphones or other device onto the head of the user or other body partand that monitor ear patterns or other body part patterns to determinehow the headphones or other device is being worn by the user. Based onknowledge of the orientation of the headphones on the user's head orother orientation information, the headphones or other electronic devicecan be configured appropriately. For example, left and right stereoheadphone channel assignments may be placed in a normal or reversedconfiguration, and other device settings may be changed. If desired,user input such as touch input may be used to adjust media playbacksettings and other device settings.

Touch sensor structures may be formed from thin layers of fabric, thinprinted circuit substrates, and other thin layers of other material andmay therefore sometimes be referred to touch sensor layers. The touchsensor layers in an electronic device may be formed on rigid substratessuch as rigid primed circuit board layers and/or may be formed onflexible substrates (e.g., flexible printed circuit material such asflexible layers of polyimide or sheets of other flexible polymermaterial). In some configurations, touch sensor structures may be formedfrom printed coatings on a fabric or from conductive yams or otherstrands of material in a fabric.

In general, the strands of material that form the fabric may bemonofilaments, may be multifilament strands (sometimes referred toherein as yams), may be formed from metal (e.g., metal monofilamentsand/or yams formed from multiple monofilament wires), may be formed fromdielectric (e.g., polymer monofilaments and yams formed from multiplepolymer monofilaments), may include dielectric cores covered withconductive coatings such as metal (e.g., metal coated dielectricmonofilaments and yarns of metal coated polymer-core monofilaments maybe used to form conductive monofilaments and conductive yarns,respectively), may include outer insulating coatings (e.g., coatings ofpolymers or other dielectrics may surround each metal-clad polymermonofilament or each collection of metal-clad polymer monofilaments in ayarn, polymer insulation may enclose a multifilament metal wire, etc.),or may be other suitable strands of material for forming fabric.Configurations in which the fabric is formed from yarns (e.g.,multifilament strands of material that are insulating or that containmetal wires and/or metal coatings on polymer monofilaments to render theyams conductive) may sometimes be described herein as an example. Thisis, however, merely illustrative. The fabric may be formed usingmonofilaments, multifilament strands of material (yams), combinations ofthese arrangements, etc. The fabric may be woven, knitted, braided, ormay contain yarns or other strands of material that have beenintertwined using other intertwining techniques. Touch sensor structuresmay be formed on the ear cups in a pair of headphones or on otherportions of an electronic device.

FIG. 1 is a schematic diagram of an illustrative electronic device. Asshown in FIG. 1, electronic device 10 may communicate wirelessly withexternal equipment such as electronic device 10′ using wireless link 28.Wireless signals for link 28 may be light-based signals, may be acousticsignals, and/or may be radio-frequency signals (e.g., wireless localarea network signals, Bluetooth® signals, radio-frequency signals incellular telephone band, signals at 60 GHz, near field communicationssignals, etc.). Equipment 10 and equipment 10′ may have antennas andwireless transceiver circuitry for supporting wireless communicationsover link 28. Equipment 10′ may have the same capabilities as equipment10 (i.e., devices 10 and 10′ may be peer devices) or equipment 10′ mayinclude fewer resources or more resources than device 10.

Illustrative device 10 of FIG. 1 has control circuitry 20. Controlcircuitry 20 may include storage and processing circuitry for supportingthe operation of device 10. The storage and processing circuitry mayinclude storage such as hard disk drive storage, nonvolatile memory(e.g., flash memory or other electrically-programmable-read-only memoryconfigured to form a solid state drive), volatile memory (e.g., staticor dynamic random-access-memory), etc. Processing circuitry in controlcircuitry 20 may be used to control the operation of device 10. Theprocessing circuitry may be based on one or more microprocessors,microcontrollers, digital signal processors, baseband processors, powermanagement units, audio chips, application specific integrated circuits,etc.

Input-output circuitry in device 10 such as input-output devices 22 maybe used to allow data to be supplied to device 10 and to allow data tobe provided from device 10 to external devices. Input-output devices 22may include buttons, joysticks, scrolling wheels, touch pads, key pads,keyboards, tone generators, vibrators, cameras, sensors 26 (e.g.,ambient light sensors, proximity sensors, magnetic sensors, forcesensors, touch sensors, accelerometers, and other sensors),light-emitting diodes and other status indicators, data ports, displays,etc. Input-output devices 22 may include audio components 24 such asmicrophones and speakers (e.g., left and right speakers in a pair ofearbuds, in ear cups in over-the-ear headphones, in ear cups inon-the-ear headphones, or other earphones). A user can control theoperation of device 10 by supplying commands through input-outputdevices 22 and may receive status information and other output fromdevice 10 using the output resources of input-output devices 22.

Control circuitry 20 may be used to run software on device 10 such asoperating system code and applications. During operation of device 10,the software running on control circuitry 20 may use sensors 26 andother input-output devices 22 in device 10 to gather input from a user.A user may, for example, supply touch input using one or more fingersand/or other external objects (e.g., a stylus, etc.). Touch sensor inputmay also be gathered from touch sensors in contact with the ears of auser (or in contact with other body parts). This touch sensor input mayhelp device 10 determine the orientation of device 10 with respect tothe user's head or other body part. For example, by identifying whichear cup of a pair of headphones is covering the right ear of the userand which ear cup is covering the left ear, device 10 can determinewhether the headphones are being worn in an unreversed or in a reversedconfiguration and can make audio adjustments accordingly (e.g., byadjusting left/right channel assignments).

Electronic device 10 (and external equipment 10′) may, in general, beany suitable electronic equipment. Electronic device 10 (and device 10′)may, for example, be a computing device such as a laptop computer, acomputer monitor containing an embedded computer, a tablet computer, acellular telephone, a media player, or other handheld or portableelectronic device, a smaller device such as a wrist-watch device (e.g.,a watch with a wrist strap), a pendant device, a headphone or earpiecedevice, a device embedded in eyeglasses or other equipment worn on auser's head, or other wearable or miniature device, a television, acomputer display that does not contain an embedded computer, a gamingdevice, a navigation device, an embedded system such as a system inwhich electronic equipment with a display is mounted in a kiosk orautomobile, equipment that implements the functionality of two or moreof these devices, or other electronic equipment. FIG. 2 is a perspectiveview of an illustrative electronic device. In the illustrativeconfiguration of FIG. 2, device 10 is a portable device such as a pairof headphones (earphones). Other configurations may be used for device10 if desired. The example of FIG. 2 is merely illustrative.

As shown in FIG. 2, device 10 may have ear cups such as ear cups 30.There may be two ear cups 30 in device 10 that are coupled by a supportsuch as band 34. Band 34 may be flexible and may have a curved shape toaccommodate a user's head. There may be left and right ear cups 30 indevice 10, one for one of the user's ears and the other for the otherone of the user's ears. Each ear cup may have an area such as area 32through which sound may be emitted from a speaker (e.g., a speakersystem with one or more drivers). When worn in an unreversedconfiguration, the right ear cup of device 10 will supply audio to theright ear of the user and the left ear cup of device 10 will supplyaudio to the left ear of the user. In a reversed configuration, theright ear cup is adjacent to the user's left ear and the left ear cup isadjacent to the user's right ear. For correct audio playback, theassignment of the left and right channels of audio that are being playedback to the user can be reversed (so that the left channel of audio isplayed through the right ear cup and vice versa) whenever device 10 isbeing worn in the reversed configuration. Unreversed right-left channelassignments may be used when device 10 is being worn in the unreversedconfiguration.

Device 10 may have an asymmetrical design or may have a symmetricaldesign. A symmetrical design may be used to provide device 10 withenhanced aesthetics. In sonic configurations for device 10 (e.g., whendevice 10 has a symmetrical design), there may be few or no recognizabledifferences between unreversed and reversed orientations for device 10.In this type of scenario, it may be desirable to use touch sensor inputor input from other sensors 26 to determine whether to operate device 10in an unreversed audio playback or reversed audio playbackconfiguration.

To gather input from device 10, one or more of the external surfaces ofband 34 and/or ear cups 30 may be provided with input-output devices 22such as sensors 26. As an example, touch sensors or other sensors may beprovided on inner ear cup surfaces 30-1 to measure a user's ear shapes,may be provided on opposing outer ear cup surfaces 30-3 (e.g., to gatherinput from a user's fingers or other external objects), and may beprovided on the intermediate portions of the surfaces of ear cups 30such as circumferential surfaces 30-2, which run around the periphery ofcups 30 between inner surfaces 30-1 and outer surfaces 30-3 (e.g., togather user grip information and other input).

Touch input to surfaces such as surfaces 30-1, 30-2, and/or 30-3 mayinclude multi-touch input (e.g., simultaneous touch input from multiplelocations), multi-touch gesture input and other gestures (e.g., swipes,finger pinches, taps, etc.), touch data associated with temporarycontact with the user's fingers while ear cups 30 are being held by auser who is putting device 10 on the user's ears, touch data associatedwith the (potentially prolonged) contact between touch sensor arrays oninner surfaces 30-1 and the ears of the user, or other touch input.Non-touch input from a user and/or the environment surrounding device 10may also be gathered using sensors 26.

A cross-sectional side view of a portion of device 10 of FIG. 2 is shownin FIG. 3. As shown in FIG. 3, band 34 may have band walls 34H (e.g.,plastic walls, fabric walls, walls formed from metal or other materials,etc.). Electrical components 38 (e.g., control circuitry 20 and/orinput-output devices 22, batteries, and/or other electrical circuitry)may be mounted on one or more substrates such as substrate 36 (e.g., aprinted circuit such as a rigid printed circuit board formed fromfiberglass-filled epoxy or other rigid printed circuit board material ora flexible printed circuit having a substrate formed from a flexiblepolymer such as a sheet of polyimide). Metal traces and other signalpaths 40 may be used to couple circuitry 38 to sensor structures 44 onthe surfaces of ear cups 30 and may be used to couple circuitry 38 tospeakers 42. Each ear cup 30 may have a region such as region 32 throughwhich sound is emitted from a corresponding speaker 42 while inner cupsurfaces 30-1 are being worn against the user's head (e.g., on or overthe user's ears). Region 32 may have an opening (e.g., a speaker port)and/or may be covered with an acoustically transparent material such asfabric, open cell foam, a metal or plastic structure with an array ofopenings, etc.

Sensor structures 44 may be formed on inner surfaces 30-1, outersurfaces 30-3, and intermediate surfaces 30-2 and may include touchsensors and other sensors 26. Sensor structures 44 may include touchsensor structures formed from yarns of conductive material (e.g.individual conductive yams woven within a non-conductive fabricstructure to form a capacitive touch sensor array), from conductivematerials (e.g., conductive ink) that is printed in patterns on ear cups30 (either directly on ear cups, or printed onto a laminatefilm/adhesive/intermediate layer that is then adhered to the ear cups),from metal traces on printed circuits and other substrates, frompatterned metal foil, from metal housing structures and other metalparts, from non-metallic structures, and from other structures.

Touch sensors in device 10 may be formed using any suitable touchtechnology. As an example, touch sensors may be formed from one or morepatterned layers of capacitive touch sensor electrodes. Other types oftouch sensor may be used in device 10 if desired (e.g., touch sensorsbased on resistive touch technology, acoustic touch technology,light-based touch sensors, etc.). In some scenarios, sensor arrays maybe provided that are sensitive to the amount of force applied by auser's body part of other external object. This type of sensor may alsogather information on the position of a user's finger or other externalobject (as with a touch sensor) but is sometimes referred to as a forcesensor because not all touch sensors are sensitive to different amountsof applied force.

If desired, hybrid sensors may be provided. A hybrid sensor may gatherinput using multiple different sensor technologies. An example of ahybrid sensor that may be used in gathering input for device 10 is ahybrid capacitive touch-force sensor. This type of sensor may makecapacitive measurements to determine where a user's touch input is beingprovided (e.g., to gather touch location information) and may make adifferent type of capacitive measurements to determine how forcefullythe user's touch input is being applied (e.g., to gather force input).

An illustrative capacitive touch sensor array is shown in FIG. 4. Touchsensor 46 of FIG. 4 is a capacitive touch sensor having touch sensorelectrodes 48 and 50. Touch sensor controller 52 may supply drivesignals to the touch sensor electrodes while gathering correspondingsense signals from the electrodes. Using this type of arrangement orother touch controller arrangement, controller 52 may make capacitancemeasurements with electrodes 48 and 52 that allow controller 52 todetermine the location of a user's touch within the electrodes (e.g.,that allow controller 52 to identify the location at which the presenceof the user's finger or other body part overlaps the array and thereforecreates a localized reduction in electrode-to-electrode capacitance).

Electrodes 48 and 50 may be formed from transparent conductive materialsuch as indium tin oxide or invisibly thin conductive lines or fromopaque materials such as metal. Electrodes 48 and 50 may be formed onone side or on opposing sides of a flexible printed circuit, may beformed as multiple layers in a touch sensor coating formed on a fabricor foam layer or other structures in device 10, may be formed usingsingle-sided electrode patterns, may be formed using double-sidedelectrode patterns, may be formed from conductive strands of material(e.g., dielectric yams coated with a conductive material and, ifdesired, an outer coating of dielectric material, metal yarns ofconductive material, etc.), may be formed using patterns ofinterconnected squares, diamonds, wedges, dots, or other capacitiveelectrode shapes, may have circular electrode shapes, may have curvedshapes (e.g., full or partial ring shapes), may have radially symmetricshapes and/or rotationally symmetric shapes, or may be formed using anyother suitable touch sensor configuration. The configuration of FIG. 4in which sets of perpendicular touch sensor capacitive electrode stripsare arranged in a grid of overlapping horizontal and vertical electrodesis merely illustrative.

If desired, an array of conductive paths for a capacitive touch sensorelectrode grid or other conductive structures in device 10 may be formedusing conductive yams (or other conductive strands of material). As anexample, consider fabric 54 of FIG. 5. As shown in FIG. 5, fabric 54 maycontain intertwined strands of material such as yams 56 and 58. Yarns 56may be warp yams and yarns 58 may be weft yams in a woven fabric orfabric 54 may be formed using other intertwining techniques (e.g.,knitting, braiding, etc.). Coatings may be formed on the upper and/orlower surface of fabric 54 (e.g., dielectric coatings and/or conductivecoatings such as metal coatings). If desired, some of yams (strands) 56and/or some of yams (strands) 58 may be conductive and may serve aselectrodes such as capacitive electrodes 48 and 50 of FIG. 4. The numberof conductive yarns the number of yarns containing conductive material)may be smaller than the number of insulating yarns (e.g., the yarnsformed from dielectric materials such as polymers) so that theconductive yarns are relatively sparse within fabric 54 or denserconstructions with more conductive yams may be used.

Components may be attached to the conductive yarns (or other strands ofmaterial) in fabric 54 (e.g., force sensors, light-based sensors, etc.).If desired, fabric 54 may be used as a covering for some or all ofdevice 10 (e.g., on some or all of surfaces 30-1, 30-2, and 30-3 orelsewhere on device 10). In this type of arrangement, touch sensors orother sensors may be formed from the fabric that is located on theexterior of device 10. Fabric may also be used in forming internalsensor structures.

If desired, a fabric-based sensor or other sensor for device 10 mayinclude force sensing components. Consider, as an example, force sensor60 of FIG. 6. As shown in FIG. 6, force sensor 60 may have a layer ofcompressible material such as material 66. Material 66 may be formedfrom polymer foam or other compressible elastomeric material, fromfabric, or other material that can be compressed when force is applied.Capacitor electrodes such as electrodes 62 may be patterned on a firstsurface of layer 66 and one or more electrodes such as illustrativeground electrode 64 may be formed on an opposing second surface of layer66. When an external object such as object 68 (e.g., a user's finger, auser's ear, etc.) is not pressing against the first surface, layer 66will not be compressed. As a result, the spacing between electrodes 62and 64 will be at a maximum and the capacitance between electrodes 62and electrode 64 will be minimized. In response to application ofpressure in direction 70 by object 68, material 66 will compress,thereby decreasing the separation distance D between at least one ofelectrodes 62 and electrode 64 as shown in FIG. 7. This creates anincrease in capacitance for the depressed electrode relative to ground64. The amount of increase is proportional to the amount of forceapplied by object 68 in direction 70, so the output of force sensor 60is a force value. The output of force sensor 60 also contains positioninformation (e.g., the identity of the location of electrode 62 in theexample of FIGS. 6 and 7), so force sensor 60 can also serve as aposition sensor that senses where a user is applying force to sensor 60.

FIG. 8 shows how a hybrid touch-force sensor may be formed using fabriclayers separated by a compressible layer. Hybrid sensor 79 has firstfabric layer 72A and second fabric layer 72B. First fabric layer 72A isseparated from second fabric layer 72B by compressible layer 78 (e.g.,foam, fabric, etc.). Each fabric layer may have strands of material suchas strands 74 and 76. In layer 72A, these strands may serve asoverlapping capacitive sensor electrodes for a touch sensor, asdescribed in connection with strands 56 and 58 of touch sensor 54 (FIG.5). In layer 72B, strands 74 and 76 may be shorted together to form aground plane (as an example). A layer of metal foil, metal traces on aprinted circuit, or other conductive materials may also be used to forma ground plane for layer 72B. When object 68 is present on the surfaceof layer 72B, the touch sensor capabilities of layer 72B may be used togather touch sensor input (i.e., information on the position of object68). When object 68 is pressed downwards, a capacitance increase isdetected between an electrode(s) in fabric 72A and the ground planeformed by layer 72B (i.e., sensor 79 produces a force-dependent outputsignal). Sensor 79 may therefore be used to gather touch sensor input(independent of touch force) and force input related respectively to theposition and force applied by object 68. The ability to gather bothtouch and force input allows a user to supply different types of inputin different usage scenarios.

If desired, sensors 26 may include touch sensors and force sensors usingother types of components. In the example of FIG. 9, touch sensor 80 hasan array of light emitters and detectors to gather touch input. Emitters84 and detectors 90 may be mounted in one or more layers of materialsuch as layer 82 (e.g., plastic, fabric, etc.). Emitters 84 may belight-emitting diodes or other light sources that produce light 86. Inthe absence of a nearby external object, light 86 is not reflected toany of detectors 90. In the presence of a nearby external object such asobject 68, light 86 is reflected to detector 90 as reflected light 88and is detected. The location of emitter 84 and detector 90 can be usedto identify the location of object 68, so an array of emitters 84 anddetectors 90 may be used as a position (touch) sensor e.g., a positionsensitive short-range proximity detector). If desired, a light-basedarray of the type shown in FIG. 9 may be used in gathering force input.Force (pressure) and/or touch input may also be gathered using otherlight-based sensors (e.g., optical time-of-flight sensors, opticalproximity sensors using other patterns of emitters and detectors, etc.).

Illustrative sensor 92 of FIG. 10 has a layer of material such asmaterial 98 (e.g., foam, plastic, fabric, etc.) and includes a layer onmaterial 98 such as layer 94 with resistors 96. Resistors 96 may bethin-film resistors or other resistors that exhibit changes inresistance as a function of applied pressure. When external object 68presses against resistors 96, the resistance changes in resistors 96 canbe detected and the location of the pressure can be identified.Resistors 96 may be arranged in an array of rows and columns or othersuitable array, may form bridge circuits (e.g., to form strain gauges),or may be mounted in other configurations. Sensor 92 may measure appliedforce (i.e., sensor 92 may be a pressure-sensitive component that servesas a force sensor) and may gather position information on applied input(e.g., sensor 92 may serve as a touch sensor).

FIG. 11 shows how device 10 may be provided with a force sensor that hasan array of force sensing elements 102. Elements 102 may bepiezoelectric elements, resistor-based strain gauges, or other straingauge elements that generate a signal responsive to applied force.Sensors 102 may be mounted in an array and may be monitored using signaltraces in associated interconnect layers such as layers 104 and 106(e.g., fabric layers, flexible polymer layers, etc.). If desired,elements 102 may use variable resistance, variable capacitance, or otherprinciples to generate force-sensitive output signals. The example ofFIG. 11 in which elements 102 are piezoelectric elements is merelyillustrative.

If desired, sensors 26 may include other types of sensors for gatheringinformation on the position and force of external objects adjacent todevice 10. The arrangements of FIGS. 4-11 are examples.

FIG. 12 is a side view of one of ear cups 30 in an illustrativeconfiguration in which a sensor has been formed on inner surface 30-1.In the example of FIG. 12, sensor 108 has an outer ring-shaped layer 110and an opposing inner ring-shaped layer 114. A compressible ring-shapedlayer of material such as layer 112 may be interposed between layer 110and layer 114. Layers 110, 112, and 114 may have central openings thatare aligned with each other and that form a passageway in region 32 toallow sound from a speaker in cup 30 to be emitted for a user. Layers110 and 114 may have patterned capacitive touch sensor electrodes (e.g.,ring-shaped electrodes that surround opening 32, etc.) that allow sensor108 to serve as a touch sensor array. If desired, sensor 108 may also besensitive to capacitance rises due to compression of layer 112 (i.e.,sensor 108 may supply force output as well as touch output so thatsensor 108 may serve as a hybrid touch-force sensor). A layer ofmaterial such as layer 118 (e.g., fabric, etc.) may cover sensor 108and/or may form part of sensor 108.

FIG. 13 shows how ear cups 30 may be provided with an array ofcapacitive touch sensor electrodes (or other touch sensor elements) suchas electrodes 120 that extend around peripheral surface 30-2 of each earcup 30. Electrodes 120 may be used to form a touch sensor that measuresthe position of user input along dimension DX of FIG. 13 (i.e., distancearound the periphery of cup 30). Touch sensors may also be formed fromarrays of electrodes on inner cup surfaces such as surface 30-1 andouter cup surface 30-3. The touch sensor on inner cup surface 30-1 maymeasure the shape of the user's ear and thereby determine whether theright or left ear is in contact with the sensor. The touch sensor onouter cup surface 30-3 may be used to gather touch input from the user'sfinger or other external object 68. If desired, the sensor that includeselements 120 and/or the sensors on inner surface 30-1 and outer surface30-3 may be hybrid touch-force sensors or other sensors, as described inconnection with FIGS. 4-12.

Using the touch sensor formed from elements 120 or other sensor onsurface 30-2, device 10 may monitor a user's fingers. When a user gripsan ear cup, the user's thumb (finger 68-1 of FIG. 14) will generally bepositioned on an opposing side of surface 30-2 from the user's otherfingers (fingers 68-2). By detecting the number of fingers in eachlocation and by identifying the grip pattern of FIG. 14 (thumb 68-1 onone side and fingers 68-2 on the other), device 10 can detect whether auser has picked up each cup 30 with a left or right hand. Based on thisinformation (i.e., by analyzing the touch input gathered by sensor 30-2around the periphery of cup 30 to discriminate between left and righthand (finger) grips, device 10 can determine whether device 10 is beingmounted on the user's head in an unreversed configuration or a reversedconfiguration. When the user's right hand is detected on the right earcup and the user's left hand is detected on the left ear cup, device 10can conclude that the user is holding device 10 in a way that allows theuser to place the right cup over the right ear and the left cup over theleft ear (i.e., device 10 will be used in the normal unreversedconfiguration). When the opposite pattern is detected (right hand gripon left cup and left hand grip pattern on the right cup), device 10 canconclude that the right and left cups will be reversed and that device10 will be placed on the user's head in a reversed configuration. Earshape measurements from sensors on surfaces 30-1 can also be used indetermining the orientation of device 10 relative to the body of theuser. If desired, additional data from sensors 26 may be used indetermining device orientation. The use of hand grip patterns and earpatterns to discriminate between unreversed and reversed orientationsfor device 10 is merely illustrative.

FIG. 15 is a diagram showing illustrative output from a touch sensorarray (or hybrid sensor, etc.) on cup surface 30-1 in the presence of auser's ear. Touch sensor elements that are not adjacent to a portion ofthe user's ear will produce little or no output, as illustrated by nullelements 124. Elements that are adjacent to a portion of the user's earwill produce a measurable output, as illustrated by elements 126. Thepattern of signals from elements 126 can be processed using a patternrecognition application running on control circuitry 20 or the resourcesof external equipment 10′. Device 10 (and/or equipment 10′) can use theresults of pattern recognition operations to determine which ear (leftor right) is adjacent to each ear cup 30 and to take suitable action.

In the illustrative arrangement of FIG. 15, the sensor array isrectangular and has sensor elements arranged in rows and columns. Otherpatterns of sensor electrodes (e.g., capacitive touch sensor electrodes)may be used if desired.

In the example of FIG. 16, potential sensor electrode locations 130 havebeen plotted against the illustrative structures of ear 132. Sensorelectrode positions 130 of FIG. 16 have been arranged in a series ofthree concentric circles (with each circle having a correspondingcircumferentially distributed set of sensor electrodes). Other patternsof sensing locations may be used, if desired.

An illustrative set of electrodes 134 and 136 that may be used ingathering capacitive touch sensor data at electrode positions 130 ofFIG. 16 is shown in FIG. 17. Electrodes 134 extend radially outwardsfrom center area 32. Circular electrodes 136 have ring shapes thatextend around area 32 and that cross radially extending electrodes 136at locations 130 of FIG. 16. The circular array of FIG. 16 may be usedon circular portions of ear cups 30 such as inner portions 30-1 (tomonitor ear shape) and outer portions 30-3 (to gather touch input form auser's finger).

Another illustrative arrangement for electrodes in the touch sensor forear cup 130 is shown in FIG. 18. With this arrangement, a circularring-shaped ground plane having inner boundary 140 and outer boundary142 is overlapped with a series of bisected concentric ring electrodes146. In the configuration of FIG. 19, curved (ring-shaped) electrodes146 have been divided into four quadrants. This is merely illustrative.Electrodes with different numbers of radially extending andcircumferentially extending divisions may be used, if desired. Moreover,sensor input from ear sensors and/or finger sensors can be used inconjunction with other sensor data from sensors 26 to help identify userinput, device orientation, and other operating conditions for device 10.

FIG. 20 is a flow chart of illustrative steps involved in operatingdevice 10. As shown in FIG. 20, device 10 (and, if desired, externalequipment 10′) may be operated normally at step 150 while gatheringsensor data. For example, equipment 10′ may stream wireless audiocontent to device 10 while playing corresponding video or other contenton a display or other output device. Device 10 may receive thewirelessly transmitted audio and may play the audio to a user throughspeakers 42 (FIG. 3). Before playing the audio and/or while playingaudio, device 10 may gather sensor data from touch sensors, forcesensors, hybrid touch-force sensors, or other sensors on ear cups 30and/or from other sensors 26. Control circuitry 20 in device 10 and, ifdesired, control circuitry in device 10′ may analyze the sensor data.For example, the sensor data may be analyzed to determine which of theuser's ears is in contact with each ear cup 30 and/or to determine whichof the user's hands is gripping each ear cup 30, thereby determining theorientation (unreversed or reversed) of device 10 relative to the user'sears and head. Sensor data may also be gathered to determine whether auser's finger 68 has been placed at a particular location alongdimension DX on surface 30-2 or a particular location on surface 30-1.Force input and single-touch and/or multi-touch gesture input may alsobe measured using sensors on surfaces. 30-1, 30-2, and/or 30-3.

The input that is gathered during the operations of step 150 may bepassive user input (e.g., when a user's ear shape and/or hand grip isbeing measured to discriminate between the left and right ears and todiscriminate between the left and right hands without the consciousinvolvement of the user), may be environmental input (e.g., ambienttemperature, ambient light level, etc.), and/or may be active user input(e.g., active user touch input such as user gestures, user force input,etc.). Passive user input may serve as biometric information (e.g., toidentify different users of device 10 by their potentially distinctiveear shapes). Environmental sensor data (ambient light conditions,ambient temperature, location information, etc.) may help adjust theoperation of device 10 to suit current environmental conditions (as anexample).

Actively supplied user input can be used to adjust the operation ofdevice 10 and device 10′. For example, active user input (e.g., touchinput, force input, etc.) may be use to adjust media playback operations(pause, stop, play, fast forward, rewind, next track, skip tracks, othertrack controls, menu selections, etc.), may be used as gaming input(e.g., when device 10 is used as an input controller for a game), may beused to make on-screen menu selections (e.g., when a user is watchingcontent on a display on equipment 10′), or may be used to otherwisecontrol the operation of device 10 and/or device 10′. These adjustmentsmay be made at device 10 (e.g., to mute speaker output temporarily)and/or at device 10′ (e.g., to pause media playback by temporarilypausing the process of wirelessly streaming content from device 10′ todevice 10, etc.). As a user is listening to audio, for example, the usermay move a finger along dimension DX on surface 30-2. Electrodes 120 orother touch sensor structures may measure the location and movement ofthe user's finger and may adjust audio playback volume or other mediaplayback settings accordingly. In this way, a user can make adjustmentsto the settings of device 10 and device 10′ without need to identify thelocations of particular buttons on device 10.

If no desired change in operation is detected at step 150 (e.g., ifdevice 10 is oriented as expected on the user's head, if no user inputor other input is received that is suitable for making a change inoperating setting for device 10, etc.), processing may loop back to step150, as indicated by line 152.

If, however, it is determined that device 10 is being worn in a way thatrequires a change in operation for device 10 or device 10′ (e.g., if itis determined that device 10 is being worn in a reversed configuration,if user input is detected, etc.), device 10 and, if desired, device 10′can take suitable actions in response at step 154. During the operationsof step 154, device 10 can reverse audio playback so that right and leftchannel assignments are reversed to accommodate a reversed orientationfor device 10 on the user's head, may make adjustments to media playbacksettings (in device 10 and/or device 10′) and can otherwise adjust theoperation of device 10 and device 10. Operations can then loop back tostep 150, as indicated by line 156.

In accordance with an embodiment, an electronic device that providescontent to a user having fingers is provided that includes controlcircuitry, ear cups containing speakers, and touch sensors on at leastone of the ear cups that detect touch input from the fingers of theuser.

In accordance with another embodiment, the control circuitry plays audiothrough the ear cups in accordance with left and right channelassignments and the control circuitry determines whether to reverse theleft and right channel assignments in response to the touch input.

In accordance with another embodiment, the touch input includes inputfrom a plurality of the fingers and the control circuitry discriminatesbetween right hand grips and left hand grips on the ear cups using theinput from the plurality of the fingers.

In accordance with another embodiment, the control circuitry determineswhether the ear cups are to be worn by the user in an unreversed or areversed configuration in response to discriminating between the rightand left hand grips.

In accordance with another embodiment, the control circuitry reversesthe left and right channel assignments in response to determiningwhether the ear cups are to be worn by the user in an unreversed or areversed configuration.

In accordance with another embodiment, the control circuitry receiveswireless content from external equipment and the control circuitry playsaudio for the wireless content through the speakers.

In accordance with another embodiment, the control circuitry adjustsplayback of the audio in response to the touch input.

In accordance with another embodiment, the ear cups have inner surfacesthat rest against ears of the user and the touch sensors includecapacitive touch sensor electrodes on the inner surfaces of the earcups.

In accordance with another embodiment, the control circuitry uses datafrom the capacitive touch sensor electrodes to discriminate between leftand right ears.

In accordance with another embodiment, the capacitive touch sensorelectrodes include radially extending electrodes.

In accordance with another embodiment, the capacitive touch sensorelectrodes include ring-shaped electrodes.

In accordance with another embodiment, the capacitive touch sensorelectrodes include a plurality of concentric ring-shaped electrodes anda plurality of overlapping radially extending electrodes.

In accordance with an embodiment, headphones that play audio for a userhaving ears are provided that include left and right ear cups havingrespective left and right speakers with which the audio is played forthe user, sensors on the left and right ear cups that sense fingerpositions on the left and right ear cups as the user grips the ear cupsduring placement of the headphones on the ears of the user, and controlcircuitry that uses the sensed finger positions to select betweenunreversed and a reversed channel assignment configurations when playingthe audio for the user.

In accordance with another embodiment, the control circuitry plays leftchannel audio through the left speaker and plays right channel audiothrough the right speaker in the unreversed channel assignmentconfiguration and the control circuitry plays right channel audiothrough the left speaker and left channel audio through the rightspeaker in the reversed channel assignment configuration.

In accordance with another embodiment, the sensors include touchsensors.

In accordance with another embodiment, the sensors include fabric withconductive strands that form capacitive touch sensor electrodes for thetouch sensors.

In accordance with another embodiment, the sensors include force sensorshaving capacitor electrodes separated by a compressible layer that iscompressed in response to applied force.

In accordance with another embodiment, the sensors each include at leastone layer of fabric with conductive strands that form capacitive touchsensor electrodes and at least one compressible layer that is compressedin response to applied force to produce a capacitor increase that isindicative of an amount of applied force.

In accordance with another embodiment, the left and right ear cups haveinner surfaces that rest against the ears and the headphones includecapacitive touch sensor arrays on the inner surfaces that monitor carshape to discriminate between left and right ears.

In accordance with an embodiment, headphones that are worn by a user areprovided that include speakers, control circuitry that plays audiothrough the speakers in an unreversed configuration in which leftchannel audio is played through a first of the speakers that is adjacentto a left ear of the user and right channel audio is played through asecond of the speakers that is adjacent to a right ear of the user or areversed configuration in Which the right channel audio is playedthrough the first speaker that adjacent to the left ear and the leftchannel audio is played through the second speaker that is adjacent tothe right ear, and capacitive touch sensors with ring-shaped capacitivetouch sensor electrodes, the control circuitry selects between theunreversed and the reversed configuration to play audio using thecapacitive touch sensors.

In accordance with another embodiment, the headphones include ear cups,each of the ear cups includes a respective one of the speakers, thecapacitive touch sensors are located on inner surfaces of the ear cups,and each of the ring-shaped capacitive touch sensor electrodes surroundsone of the speakers.

In accordance with another embodiment, the headphones include additionaltouch sensors on the ear cups with Which the control circuitry measuresfinger positions as the user grips the ear cups.

In accordance with an embodiment, an electronic device that is worn onthe ears of a user is provided that includes control circuitry, ear cupscontaining speakers, and pressure sensors on the ear cups that gatherinformation on the ears of the user.

In accordance with another embodiment, the control circuitry plays audiothrough the ear cups in accordance with left and right channelassignments and the control circuitry determines whether to reverse theleft and right channel assignments based on the information on the earsfrom the pressure sensors.

In accordance with another embodiment, the control circuitry reversesthe left and right channel assignments in response to determiningwhether the ear cups are to be worn by the user in an unreversed or areversed configuration, the control circuitry receives wireless contentfrom external equipment, and the control circuitry plays audio for thewireless content through the speakers.

In accordance with another embodiment, the pressure sensors includepressure sensors selected from the group consisting of force-sensitiveresistors, optical sensors, strain gauges, and capacitive force sensors.

The foregoing is merely illustrative and various modifications can bemade by those skilled in the art without departing from the scope andspirit of the described embodiments. The foregoing embodiments may beimplemented individually or in any combination.

What is claimed is:
 1. An electronic device that is worn by a user, theelectronic device comprising: speakers; ear cups having inner surfacesand opposing outer surfaces, wherein each of the ear cups includes arespective one of the speakers and wherein each of the ear cups have aninner opening and a peripheral portion on the inner surface thatsurrounds the inner opening; and sensors on the inner surfaces of theear cups that extend from the inner opening to the peripheral portion.2. The electronic device defined in claim 1 wherein the sensors comprisean array of touch sensors that detect whether the ear cups are incontact with ears of the user.
 3. The electronic device defined in claim2 wherein each of the touch sensors of the array of touch sensorscomprises electrodes that make capacitive measurements to determinewhether the ear cups are in contact with the ears of the user.
 4. Theelectronic device defined in claim 3 wherein the array of touch sensorsis a rectangular array and wherein the electrodes are arranged in rowsand columns that extend from the inner opening to the peripheral portionof the ear cups.
 5. The electronic device defined in claim 3 wherein theelectrodes are ring-shaped electrodes that at least partially surroundthe inner opening and wherein the ring-shaped electrodes extend from theinner opening to the peripheral portion of the ear cups.
 6. Theelectronic device defined in claim 5 wherein the array of touch-sensorsincludes at least three concentric ring-shaped electrodes.
 7. Theelectronic device defined in claim 5 wherein the ring-shaped. electrodesare bisected into first and second halves, wherein the first half of thering-shaped electrodes is on a first side of the inner opening, andwherein the second half of the ring-shaped electrodes is on a secondside of the inner opening, opposite the first side.
 8. The electronicdevice defined in claim 5 wherein the ring-shaped electrodes are splitinto quadrants, wherein first and second quadrants of the ring-shapedelectrodes are formed on a first side of the inner opening, and whereinthird and fourth quadrants of the ring-shaped electrodes are formed on asecond side of the inner opening, opposite the first side.
 9. Theelectronic device defined in claim 5 wherein the array of touch sensorsfurther comprises radially extending electrodes that extend from theinner opening to the peripheral portion and that intersect thering-shaped electrodes.
 10. The electronic device defined in claim 2wherein one of the ear cups is a right ear cup and one of the ear cupsis a left ear cup, the electronic device further comprising: controlcircuitry that is configured to determine whether a right ear and a leftear of the user are respectively adjacent to the right and left earcups, and wherein the control circuitry is configured to: in response todetermining that the right and left ears are respectively adjacent tothe right and left ear cups, play audio out of the speakers in anunreversed configuration, and in response to determining that the rightand left ears are respectively adjacent to the left and right ear cups,play audio out of the speakers in a reversed configuration.
 11. Theelectronic device defined in claim I wherein the sensors comprise hybridforce-touch sensors that make first capacitive measurements to determinewhether an ear of the user is adjacent to the sensors and secondcapacitive measurements to determine whether the ear is applying a forceto the ear cup.
 12. The electronic device defined in claim 11 whereinthe hybrid force-touch sensors comprise first and second electrodesseparated by a layer of compressible elastomeric material. 13.Headphones that play audio into left and right ears of a user, theheadphones comprising: left and right ear cups having respective leftand right speakers that respectively play first and second audio intothe left and right ears of the user in an unreversed configuration andthat respectively play the first and second audio into the right andleft ears of the user in a reversed configuration; sensors on innersurfaces of the left and right ear cups, wherein the sensors extend froman inner portion to a peripheral portion of the ear cups and wherein thesensors are configured to determine whether the left and right ears ofthe user are respectively adjacent to the left and right ear cups; andcontrol circuitry that is configured to play audio in the unreversedconfiguration in response to determining that the left and right earsare respectively adjacent to the left and right ear cups and that isconfigured to play audio in the reversed configuration in response todetermining that the right and left ears are respectively adjacent tothe left and right ear cups.
 14. The headphones defined in claim 13wherein the ear cups have inner openings that overlap the speakers andwherein the sensors include radially extending electrodes that extendfrom the inner opening to the peripheral portion of each ear cup. 15.The headphones defined in claim 14 wherein the sensors further comprisering-shaped electrodes that intersect the radially extending electrodesto provide capacitive touch sensor measurements.
 16. The headphonesdefined in claim 13 further comprising: capacitive touch sensors on anouter edge portion of the left and right ear cups, wherein thecapacitive touch sensors are configured to receive touch input from theuser, and wherein the control circuitry is configured to adjust theaudio based on the received touch input.
 17. The headphones defined inclaim 16 wherein the capacitive touch sensors are configured to receivea swipe gesture from the user along the outer edge portion and whereinthe control circuitry is configured to change a volume of the audio inresponse to the swipe gesture.
 18. Headphones that are worn by a user,the headphones comprising: speakers; ear cups, wherein each of the earcups includes a respective one of the speakers and wherein each of theear cups has an inner opening and a peripheral portion; and capacitivetouch sensors with ring-shaped capacitive touch sensor electrodeslocated on inner surfaces of the ear cups, wherein each of thering-shaped capacitive touch sensor electrodes surrounds one of thespeakers, and wherein the ring-shaped capacitive touch sensor electrodesextend from the inner opening to the peripheral portion.
 19. Theheadphones defined in claim wherein the ear cups include right and leftear cups, the headphones further comprising: control circuitryconfigured to determine whether a right ear of the user and a left earof the user are respectively adjacent to the right and left ear cupsbased on measurements taken by the capacitive touch sensors.
 20. Theheadphones defined in claim 19 wherein the capacitive touch sensorsfurther comprise radially extending electrodes that intersect thering-shaped capacitive touch sensor electrodes and that extend from theinner opening to the peripheral portion.